Evaporator unit



Jan. 28, 1947. g, c, JOHN -O 2,414,952

EVAPORATOR UNIT v I Filed Sept. 8, 1944 Been/ma 6. damn-01v.

- cabinet, excessive I Patented Jan. 28 1947 1 nma e c. Johnson, Mundeleln,

111., assignor to Hondaille-Hershey Corporation, Detroit, Mich., a corporation of Michig Application September 8,

5 Claims.

This invention relates to heat exchangers having header chambers and spent fluid conveying ducts extending above the header chambers to insure complete usage of heat exchange fluid before it leaves the heat exchanger.

Specifically the invention deals with a stamped sheet metal evaporator unit having a bottom and' side walls containing refrigerant-distributing ducts together in the side walls and spent the header chambers in the -side walls. The inwithheader chambers refrigerant ducts extending above 1944,- Serial No. 553.194

vention utilizes portions of evaporator side walls to not only suspend the evaporator top wall of a refrigerator cabinet refrigerated shelf of the unit beneath the liner of pacityfrom the refrigerant.

The sheet metal U-shaped evaporator units as commonly used in'do'mestic mechanical refrigerators are usually suspended from the top wall of the refrigerator cabinet. In some cases, it is undesirable to have heat-absorbing evaporatorsurfaces closely adjacent the walls of the cabinet, because the cooling effect of these surfaces tends to induce frost formation on the cabinet walls. In installations where the top wall of the evapfrosting of this liner wall occurs and, upon defrosting the unit, it is very dimcult to remove the water between the unit and the top wall of the refrigerator. I

According to the present invention, portions of the side walls of a U orator unit are utilized to space the top shelf of the unit sumciently beneath the top liner of the I It is, then, an object of the present invention to provide heat exchanger units with discharge vide a U-shaped -shaped sheet metal evapducts in portions of the unit serving to mount the unit in desired relationship to a support.

of the units.

A specific object of the invention is to provide a sheet metal evaporator unit with side wall mounting portions that space heat-absorbing surfaces of the unit from a tain spent refrigerant ducts.

Another. specific object of the invention is to utilize the from the refrigerant.

A still further object of the invention is to prosheet metal evaporator unit hav- "passages.

A still further object of the invention is to provide a sheet metal U -shaped evaporator unit back to the header chambers.

0 Other and further important objects of this On the drawing:

view of an evaporator unit according to thisinvention mounted in a refrigerator cabinet.

Figure 2 is a top unit of Figure 1.

Figure 3 is a side elevational view of the evap orator unit of Figure 1.

As shown on the drawing: In Figure 1, the reference numeral l0 designates generally a refrigerator. cabinet having a |l,-and side liner walls a. chamber 0. A heat support, and also conmetal *n a sheet metal evaporator unit Figure 1 is a fragmentary front end elevational plan view of the evaporator the side walls lib,

lib, lib of the bers in the side refrigerant from frigerate the shelf.

unit li of this invention is mounted in the chamher in spaced relation from the liner walls ll and I2 by means of suspension bolts ll secured in the top wall of the cabinet l0.

The unit I3 is composed of embossed brazed or welded-together metal sheets or plates, including an inner sheet l5 and an outer sheet IS. The sheets l5 and I6, after being secured together, are bent so as to provide a bottom lia, spaced opposed vertical side wall portions lib, lib, and inturned top flanges lic, lie at theupper ends of the side wall portions lib, lib.

is composed of a pair' ducts provided by lie. The inner sheets or plates, including a top sheet 20 and a bottom sheet 2 l A back wall 22 is provided for the unit. This back wall 22 has peripheral flanges 22a around the edges thereof respectively riveted to the rear end of the shelf Hi, the side walls lib, lib, and the bottom wall lia by means of rivets 23. The back wall 22 is 22b to stiffen the same, metal can be used.

The outer sheet l6 bossment 24 extending from of the bottom of the unit l0 has an emthe front to the rear lid of the unit midway between lib. This embossment 24 cooperates with the inner inlet manifold duct for the unit.

The outer sheet Ii has a. plurality of spaced parallel embossments 25 extending from the embossment 24 along the bottom lid and side walls unit to merge into enlarged embossments 26, 26 extending in a front-to-rear direction along the side walls lib, lib at levels beneath thev shelf l8. The inner sheet I! has similar embossments .28 aligned with the embossments 26 on the outer sheet, and the aligned embossments cooperate to define header chamwalls of the unit for receiving the upper end of the refrigerant distributing ducts provided by the embossments The top sheet 20 of the shelf l8 has an embossment 21 extending along its'rear edge and equipped with a nipple portion 21a at one end thereof receiving a tube 28 which extends in back of the unit ID to an embossed nipple portioniia of the embossment provided by the embossments 21 and 24.

The bottom sheet 21 of the shelf l8 has a serpentine embossment 29 defining a duct commuduct provided by the embossment 21 and extending to the front end of the shelf ure 2, and thence rearwardly to a nipple 30 provided on the top sheet 20. This nipple ill reeeives a tube il.

Refrigerant is fed to the unit l3 through the tube 3| and flows through the duct provided by the embossment 29 and through-the duct provided by the embossment 21 of the shelf to re- Refrigerant from the shelf news from the tube 28 to the manifold duct provided by the embossment 24. This manifold duct distributes the refrigerant to the distributing also preferably embossed as at so that very light gauge sheet l5 to provide an as shown in dotted lines in Figouter sheet Ii 'the header chambers so that entrained in the spent refrigerant vapor, if presthe evaporator v the embossments 25. The refrigerant boils out of-the tops of the distributing ducts into the header chambers provided by the embossments 2i.

Serpentine embossments i2 are provided in the of the unit li to form spent refrigerant ducts in the portions of the side walls lib which lieabove the header chambers. The embossments i2 are arranged so that the spent erefrigera'nt ducts communicate with the front ends of the' respective thence .wind upwardly along a constantly inclined path to levels just beneath the flanges lic,

sheet lb of the unit l3. has nipples ii embossed thereon in communication with the discharge ends of the ducts provided by the embossments 32. These nipples receive discharge tubes il.

- Spent refrigerant vapor from the header chambers rises upwardly through the ducts provided by the embossments 32 to the discharge tubes il. Any unspent refrigerant entrained in the spent refrigerant vapor will absorb heat since the spent refrigerant ducts have heat-absorbing areas and are integral with the side wall portions of the unit above, the shelf l8. The spent refrigerant ducts, in addition, slope constantly backward toward liquid refrigerant ent in quantities which are not completely vaporized, willflow back to the header chambers. The spent refrigerant ducts are substantially horizontally disposed, but continually slope back to provide for a counter-current flow of spent and unspent refrigerant therein.

The shelf I8 is refrigerated, since it receives refrigerant from the inlet tube ill and conveys this refrigerant throughthe transfer tube 28 to unit proper. The inlet manifold of the evaporator unit then distributes the refrigerant through the refrigerated; ducts in the header chambers and spent refri erant from the header chambers is conveyed in the outlet tubes 34 through the spent refrigerant ducts lying above th header chambers and above the shelf l8. The

spent refrigerant ducts are provided in portions of the side walls of the unit which are utilized to space the refrigerated shelf l8 from the top liner ll so that the liner ll will not be frosted.

- From the above-descriptions it will be understood that the heat exchangers of this invention utilize wall areas to space heat-absorbing sur- 2| for connecting the ducts faces thereof from surrounding surfaces, while providing'ducts for spent heat exchange fluid.

It will, of course, be understood that various details of construction may be varied through a wide range without departing from the principles of this invention and it is, therefore, not the purpose to limit the patent granted hereon otherwise than necessitated by the scope of the appended claims.

I claim as my invention:

1. A heat exchanger comprising a U-shaped member having headersin the side legs thereof in spaced relation beneath the upper ends of the side legs, ducts extending around the side legs and bottom of the U-shaped member communicating with the headers, inturned flanges on the tops of the legs above the headers, serpentine ducts having superimposed elongated runs in the portions of the legs between the headers and the flanges communicating with the tops of the headers to convey spent heat exchange fluid from th( headers, and spent refrigerant outlets at the upper rear ends of the serpentine ducts.

header chambers andv 1 to define a header chamber in each vertical side in spaced relation from the top thereof, a second pair of secured-together contiguous metal sheets secured to said vertical sides above said headers and below the tops of said sides, and additional embossments in the portions of said sides between said headers and the tops of the sides providing ducts for spent heat exchange fluid from said headers. j

3. An evaporator unit comprising a pair of contiguous bonded-together metal sheets bent to form the bottom and side walls of a sharp freezing chamber, said sheets being embossed to define refrigerant-distributing ducts along the bottom and side walls and header chambers in the side walls intermediate the tops and b'ottoms thereof communicating with said ducts, a second pair of contiguous secured-together metal sheets providing a shelf with an embossed refrigerantcirculating duct, means securing said shelf to said side walls at a level adjacent the tops of the header chambers in the side walls, said side walls having mounting flanges at the upper ends thereof spaced materially above said shelf, and the portion of said side walls between said header chambers and said flanges being embossed to provide serpentine refrigerant-conveying ducts com- 6 municating with the tops ofthe header chambers and having superimposed oppositely inclined portions extending from the'front to the rear of the unit and arranged to drain refrigerant back into the header chambers, a refrigerant supply tube communicating with one end of-the duct in the shelf, a connecting tube joining the other end of said duct in the shelf with said refrigerant-distributing ducts, and spent refrigerant-receiving tubes communicating with the upper ends of the ducts above the header chambers.

4. In an evaporator unit having header chambers in the side walls thereof the improvement of side wall portions extending vertically above said header chambers and containing refrigerantconveying ducts communicating with the tops of the header chambers, said ducts having superimposed inclined runs along the length of said wall portions and sloping toward the header chambers.

5'. In a U-shaped sheet metal evaporator unit having header chambers in the sides of the U, the improvement of vertical side-walls above said header chambers embossed to define serpentine spent refrigerant-conveying ducts extending to the tops of the legs and sloping'back toward the header chambers spent refrigerant bers and unspent header chambers.

to permit countercurrent flow of gases from the header chamliquid refrigerant back to the BERNARD c. JormsoN. 

